Well drilling apparatus and power plant therefor



Oct. 4, 1960 R. A. HECKEL ETAL 2,954,709

WELL DRILLING APPARATUS AND POWER PLANT THEREFOR Filed-Sept. 2, 1955 2 Sheets-Sheet 1 e/cwzzeo I. #56654 ,mee-snf. WOO/V6 I N V EN TOR$ wax arrow/544a Oct. 4, 1960 R. A. HECKEL ET AL Y 2,954,709

WELL DRILLING APPARATUS AND POWER PLANT THEREFOR Filed-,Sept. 2, 1955 2 Sheets-Sheet 2 e/c /fl20 4. #663654 roeeasrx wave INVENTORS Patented Oct. 4, 1960 WELL DRHJLING APPARATUS AND POWER PLANT THEREFOR Claims. (Cl. 74-722) This invention relates to apparatus for the drilling of wells, and is particularly directed toimprovements in multiple engine power plants for drillmg rigs using the rotary system of drilling.

Power plants employed in rotary well drilling techniques supply power for three principal requirements. The first of these is to drive the drawworks for raising the drill string out of the hole. The second is to sup-- ply power to the rotary machine which turns the drill string. The third is to drive the slush pumps which are used to deliver mud fluid through the inside of the drill string to the bit, and to bring the cuttings up to the surface.

During normal drilling operations, the power from the power plant is divided between the rotary machine and themud pumps. During the operation of raising the drill string from the hole to change the bit, the rotary machine and mud pumps are idle and the power is all directed to the drawworks for hoisting. In deep drilling, it is not uncommon to spend as much time raising and lowering the drill string in the hole for the purpose of changing the bit as it is to spend with the bit on bottom during the drilling operation. Accordingly, the trend has been toward larger and larger power plants in order to speed up the hoisting operation for the purpose of changing the bit.

The power plant employs multiple engines in order to achieve desired flexibility in driving the various units re quiring power. Consequently, the demand for-increased power has resulted in larger engine units as well as greater numbers of such units within a particular power plant. Since it is desirable that the individual engine units be substantially duplicates in order that their power may be compounded efiiciently, as Well as for standardization of design, the requirement for more power has resulted in larger individual engine units. Consequently, the power available in a single engine unit may be greater than that which can safely be used in driving the rotary machine, and therefore the danger of twist-offs of the drill pipe is increased. Another disadvantage in conventional operation of multiple-engine power plants for well drilling rigs lies in the fact that the speed of the engines is determined by the slush pump power demand and because the engines are compounded for synchronous operation, the speed of the rotary machine can be selected only from the change speed transmission and infinite speed variation is not possible. This problem sometimes becomes acute when the power plant consists of only two large engine units. When these engine units are acting ,in compound to drive one or more slush pumps the speed of the rotary machine is determined by the particular gear selection in the transmission which is interposed between the 'power plant and the rotary machine.

It is an object of this invention to provide a multiple includm a provision for limiting the power available to drive the rotary machine, and for driving the rotary machine at any desired speed.

Another object of this invention is to provide a well drilling power plant of this type in which the maximum power available on the rotary machine drive is limited by means of a hydraulic coupling of the kinetic type.

Another object is to provide a device of this type in which the torque and power control are made effective by varying the quantity of hydraulic fluid in the working circuit of the coupling.

Another object is to provide a device of this type which is associated with the number 1 engine of a multiple engine power plant for well-drilling purposes, and which device includes means whereby it may readily be inactivated in order that the maximum available power of the number 1 engine may be used for hoisting purposes.

Other and more detailed objects and advantages will appear hereinafter.

In the drawings, Figure 1 is a plan view in diagrammatic form, showing well drilling apparatus embodying our invention; and

Referring to the drawings, the power plant, generally.

designated 10, comprises a plurality of individual engine units 11, 12, and 13. These engine units are substantially duplicates, and each may comprise a single internal combustion engine or a group of such engines connected for operation as a unit. Each of the engine units is provided with a service clutch 14 for driving the respective power take-01f shafts 15, 16, and 17.

A drawworks, generally designated 18, may be of any conventional type and, as shown in the drawings, includes a spooling drum 19 having brake rims 20 fixed on a rotary drumshaft 21. A pneumatically operated friction clutch 22 serves to connect the low speed drive sprocket 23 in driving relationship with the drumshaft 21. A

.. similar clutch unit 24 is employed for connecting the engine power plant for well drilling purposes which in- 7 double sprocket member 25 to the drumshaft 21.

The low speed sprocket 23 and the double sprocket member 25 are driven from the jack shaft 26 through multiple strand chains 27 and 27 respectively. The jack shaft, in turn, is driven at any one of three speeds through chain-and-sprocket drives 28, 29, and 30. Gears 31 are provided for effecting a reverse drive when required.

The rotary machine 32 is provided with a driven sprocket 33 which receives power from the chain 34 and sprocket 35. The sprocket 35 is mounted on the countershaft 36 which is driven from the sprocket 37 and friction clutch 38. The sprocket 37 is connected to the double sprocket member 25 which is connected by means of a chain 39. From this description it will be understood that the sprocket 37, double sprocket mem- 42 which receives power from the multiple strand chain 43 and drive sprocket 44. The power of the engines may be compounded through chains 45 and 46 so that the total combined power of the engines is delivered through the cha1n 43 and sprocket 42 to the drawworks 18 for hoisting purposes.

During the drilling operation, however, With the on the bottom, the engine unit 13 may drive the slush pump 47 through the clutch 48 and belts 49. The engine unit 12 may drive a similar pump (not shown) through the clutch 56 and a drive pulley 51. The engine 11 drives the rotary machine through chains 43', 27, 39', and 34. During this drilling operation, the compounding clutches 52 and 53 are open.

As shown in Figure 2, the multiple strand'chain 46 is connected to the drive sprocket 54 which is fixed on the power take-off shaft by means of a key 55. The sprocket 44- is mounted on a rotary sleeve 56 which is supported on the shaft 15 by means of spaced bearing assemblies 57 and 58. At one end, this sleeve is provided with a drive flange 59 which is connected to a driven member 69 by means of fasteners 61.

The driven member 60 is provided with a cylindrical surface 62 on its outer periphery, and this surface is engaged by one or more series of friction drive shoes 63. These drive shoes 63 are pneumatically actuated through cylindrical rubber diaphragms 64 anchored to the driven member 65. The construction and operation of the parts as and 64 are illustrated and describedin the Picard Patent No. 2,710,287, issued June 17, 1955, entitled Air Operated Friction Clutch.

When air under pressure is supplied through the pipe 66, the shoes 63 are brought into frictional driving engagement with the cylindrical surface 62 with the result that the driving connection is established between the driving member 65 and the driven member 69. When the pressure in the pipe se is vented, the shoes 63 move outwardly and the driving connection is interrupted. The member 65 is fixed to the flange member 67, and the latter is fixed on the hub 68 which is fixed on the shaft 15 by means of the key 69.

The clutch assembly, generally designated 74 has sufficient capacity to transmit the combined power of all of the engine units in the power plant it A brake drum 1&2 may be mounted on the member 66 to receive a brake band 163 and the friction lining 104. The band 103 may be contracted by actuating means (not shown) in order to provide a friction brake to hold the members 6%), 56, and :4- stationary when desired.

A hydraulic coupling assembly 71 is mounted near the shaft 15, and this assembly includes a shaft 72 mounted in spaced bearings 73 and having an impeller 74 fixed thereto by means of a key 75. The casing or shell 76 turns with'the impeller 74. A sleeve 77 is mounted on axially spaced bearings 73 carried on the shaft 72. The runner 79 is fixed on the sleeve 77 andthe runner and impeller placed in juxtaposition to define a working circuit 80 therebetween. may be fixed on one end of the shaft 22 for the purpose of driving an oil pump (not shown).

An axially movable scoop tube 82 has one end 83 which projects into the chamber $4 defined between the shell and the outer portion of the impeller 74. This scoop tube may be thrust into and out of the central opening 85 formed in the shell 76, and its purpose is to control the quantity of hydraulic fluid in the chamber 84 and thereby control the volume of hydraulic fiuid in the working circuit 80. The scoop tube 82 is guided longitudinally and is actuated by means of a clevis 36 carried on one end of a swinging arm 87. The arm is fixed to a. crankshaft 88. The crankshaft $8 is actuated by means of a hydraulic cylinder 89 and crank arm 90.

When the scoop tube 82 is in the full line position, as shown in Figure 2, substantially all of the hydraulic fluid in the working circuit 34 is removed, with the result that no torque is transmitted from the impeller 74- to the runner 79. When the scoop tube 82 is withdrawn in an upward direction, as viewed in Figure 2, the end 83 thereof is positioned closer to the axis of rotationof the shaft 72 with the result that hydraulic fluid enters The sprocket 81' the working circuit 80, and therefore power is trans mitted from the impeller 74 to the runner 79.

Hydraulic fluid under pressure is constantly delivered to the annular cavity 91 through connections to the hydraulic pump (not shown). Hydraulic fluid passes inwardly through ports 92 and 93 to the working circuit St and immediately passes out through leak-off ports 94 into the chamber 84 to the extent permitted by the hydraulic fluid in the chamber 84. The quantity of hydraulic fluid in the working circuit 81 therefore, depends upon the quantity of fluid present in the chamber 84. The construction and operation of the scoop tube 82 are similar to that shown and described in the Dolza et al. Patent No. 2,491,483.

Drive sprocket 95 is fixed on shaft 15 by the key 95a and drives a sprocket 96-through a chain $7. The sprocket )6 is fixed on the shaft 72 by means of a key 98. The sprocket 99 is formed integrally with the sleeve 77 and drives sprocket 1th) through the chain 1-01. The sprocket is fixed on the sleeve 56.

When hydraulic fluid is present in the working circuit 80, the coupling 71 serves to transmit power from the shaft 15 to the sprocket 44, and the greater the amount of hydraulic fluid in the working circuit, the greater is the capacity for transmitting power.

It will be observed that four shaft elements are involved in the mechanism shown in Figure 2. The first is the shaft 15, the second is the countershaft 72, the third is the sleeve 56 coaxial with shaft 15, and the fourth is the sleeve 77 coaxial with the countershaft 72. Considered in this manner, the heavy duty friction clutch 7ti'connects the first and third shaft elements, while the hydraulic coupling 71 connects the second and fourth shaft elements. a

From the above description, it will be understood that two power paths are provided for driving the sprocket 44 from the shaft 15. The first of these is through the penumatically operated friction clutch '70. The second is through the hydraulic coupling 71. Accordingly, when the sprocket 44- is required to drive the drawworks for hoisting under maximum power requirements, the clutch 70 is closed. However, when the sprocket 44 transmits power for driving the rotary machine, the hydraulic coupling 71 is used in order to limit the power which may be transmitted. An excess of available power in the number 1 engine (engine unit 11), therefore, poses no threat of danger of twist-off on the drill pipe. The maximum power transmitted to the rotary machine may readily be varied by varying the position of the scoop tube 82. Furthermore, the control of the quantity of fluid in the working circuit 39 of the hydraulic coupling 71 makes it possible to vary the speed of drive of the rotary machine 32 by stepless increments between the three speeds provided by means of the chain-andsprocket drives 28, wand 30. Accordingly, the speed of the engine units may be regulated or governed for efficient operation of the slush pumps without imposing any restriction on the speed of drive of the rotary machine 32.'

The hydraulic coupling device 71 may also be used when the rotary machine requires more power than a single engine unit can deliver but less power than the total combined output of two engine units; In this case, the hydraulic coupling 71 is made large enough to transmit the maximum amount of power permitted, and the scoop tube 82 is'available to lower this maximum to any desired level.

Having fully described our invention, it is to be understood that we are not to be limited to the details herein set forth, but that our invention is of the full scope of the appended claims.

We claim:

1. In combination with a well drilling rig having a rotary machine, a hoisting mechanism and a pump, and having a plurality of engine units connected to operate in unison and adaptedto deliver their combined power to either the hoisting mechanism or to the slush p p;

a power take-off element, means whereby the power takeoff element may drive either the rotary machine or the hoisting mechanism, releasable clutch means whereby the combined power of the engine units may drive the power take-off element, a hydraulic coupling having an impeller and a runner cooperating to define a working circuit therebetween, means whereby the impeller may be driven from said engine units, means connecting the runner to drive said power take-off element, and means for varying the quantity of hydraulic fluid in the working circuit of the hydraulic coupling and thereby vary the power transmitted, whereby, upon release of said clutch means, the engine units may operate in unison to drive the slush pump while the rotary machine is driven from the hydraulic coupling.

2. In combination with a well drilling rig having a rotary machine and a pump, and having a plurality of engine units connected to operate in unison and adapted to deliver their combined power to the slush pump, a power take-01f element, means whereby the power takeoff element may drive the rotary machine, releasable clutch means whereby the engine units may drive the power take-off element, a hydraulic coupling of the kinetic type connected to be driven from said engine units, said hydraulic coupling having an impeller and a runner cooperating to define a working circuit therebetween, means for varying the quantity of hydraulic fluid in said working circuit to vary the power transmitted, and means connecting the hydraulic coupling to drive said power takeoff element, whereby, upon release of said clutch means, the engine units may operate in unison to drive the slush pump while the rotary machine is driven from the hydraulic coupling.

3. In combination with a well drilling rig having. a rotary machine, a hoisting mechanism and a slush pump, and having a plurality of engine units connected to operate in unison to deliver their combined power to either the hoisting mechanism or to the slush pump, a shaft, means whereby the slush pump and the shaft may receive power from all of the engine units, a sleeve mounted to turn on the shaft and having a power take-off sprocket fixed thereon for driving the hoisting mechanism or the rotary machine, a friction clutch assembly on said shaft for driving said sleeve from said shaft, a countershaft parallel to said shaft and having a sleeve rotatably mounted thereon, a variable-fill hydraulic coupling having an impeller fixed to the countershaft and a runner fixed to the latter said sleeve, the impeller and runner cooperating to define a working circuit therebetween for hydraulic fluid, means including a scoop tube for controlling the amount of hydraulic fluid in said working circuit, chain and sprocket means for driving the countershaft from said shaft and for connecting said sleeves for simultaneous rotation, whereby, upon release of the friction clutch the engine units may operate in unison to drive the slush pump while the rotary machine is driven from the hydraulic coupling at variable speeds in accordance with the quantity of hydraulic fluid present within said working circuit.

4. in combination with a Well-drilling rig having a rotary machine, a hoisting mechanism and a slush pump, and having a plurality of engine units connected to operate in unison to deliver their combined power to either the hoisting mechanism or to the slush pump, a first shaft member, a second shaft member laterally spaced from andparallel to said first shaft member, means whereby the slush pump and one of said shaft members may receive power from all of the engine units, a third sh aft member mounted coaxially of said first shaft member and having a power take-01f sprocket fixed thereto for driving the hoisting mechanism or the rotary machine, a friction clutch connecting said first and third shaft members, a fourth shaft member, a variable-fill hydraulic coupling having an impeller fixed to the second shaft member and a runner fixed to the fourth shaft member, the impeller and runner cooperating to define a Working circuit therebetween for hydraulic fluid, means for controlling the amount of hydraulic fluid in said working circuit, chain and sprocket means for connecting the first and second shaft members for simultaneous rotation, additional chain and sprocket means for connecting the third and fourth shaft members for simultaneous rota.- ticn, whereby, upon release of said friction clutch, the engine units may operate in unison to drive the slush pump While the rotary machine is driven from said hydraulic coupling at variable speed in accordance with the quantity of hydraulic fluid present within said working circuit.

5. In combination with a well-drilling rig having a rotary machine, a hoisting mechanism and a slush pump, and having a plurality of engine units connected to operate in unison to deliver their combined power to either the hoisting mechanism or to the slush pump, a driving member and a driven member rotatable about a common. axis, releasable clutch means adjacent one end of said driven member to form a direct primary driving connection between said members, means operatively interposed between said members providing a secondary drive to impart rotation to said driven member through the other end thereof, said means including a variable-fill hydraulic coupling connected to drive said driven member upon said clutch means being released, the filling of the hydraulic coupling being the sole means of accomplishing the secondary drive, and a power take-off element on said driven member positioned between said ends thereof.

References (Jited in the file of this patent UNITED STATES PATENTS 1,859,607 Sinclair May 24, 1932 2,399,709 Schjolin May 7, 1946 2,413,675 Baker Jan. 7, 1947 2,576,872 Young Nov. 27, 1951 

